This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Objective: To determine the accommodative ability in older rhesus monkeys following central stimulation before and after lens lasering. An electrode was implanted into the Edinger Westphal nucleus of each of 2 older rhesus monkeys so that accommodation could be stimulated centrally. In addition 4 young rhesus monkeys were used as test subjects to calibrate the femtosecond laser. Baseline testing was completed prior to determination of the effects of lens lasering on the accommodative response. The femtosecond laser procedure appears to be well tolerated in the monkey eye. However, small retinal burns (1-2 mm in size) were noted in 2 out of 5 monkeys lasered. The ability to obtain refractive measurements with the Hartinger coincidence refractometer was not compromised by the femtosecond laser procedure beginning 24 hours after lasering and the animals did not exhibit abnormal behavior or evidence of pain or discomfort. This research used WNPRC Research Services.